Your browser does not support iframes. For maximum efficiency, please upgrade to your browser's latest version or use an iframe compatible browser such as Internet Explorer, Netscape, Opera, Mozilla, Firefox, Bezilla, Galleon, WarpZilla or Lynx.

A touch soft wide open, but this is mostly noticable in daylight. It's a bit dreamy wide open in bright light. However, in dim light, when you need it, the fine detail is certainly there. Even out to the corners. Remember, even at 20mm, 1.8 is VERY shallow. My Nikons have always done well with this lens, but YMMV when it comes to focus accuracy. I believe I have some correction dialed in on my bodies. Canons seem to struggle with this lens.

There are some complaints below about having trouble focusing in low light--this is true of MOST cameras and lenses this wide or wider! Try it with lenses in the 14-16mm range and you'll see the same. It's a technical limitation, not a lens quality issue.

Also, a story about build quality and warranty repairs: the lens feels rather robustly built, but as I was transitioning from film I was using this on a D2x. The D2x and this lens destroyed each other. The aperture bladed crumpled and the aperture arm on the camera stripped. Nikon fixed the body under warranty (only a couple months old!).

The lens however was just shy of four years old, and just about to go out of warranty. It took Sigma at least EIGHT attempts to properly repair my lens so that a) the aperture blades didn't implode and b) it was as sharp as it had previously been. In seeing how this lens performed when improperly re-assembled, I can imagine that some must come from the factory that way and be very soft.

I'll give Sigma credit: they kept trying until it was fixed to my satisfaction. But you can see from this story that there is the potential quite a bit of variation in quality in the end product.

Something I don't see often in reviews of this lens is it's close focusing capabilities. It can focus VERY close--within an inch of the front element! Combined with it's wide angle of view this can make for some interesting effects. Also the bokeh is pretty neutral all around. Wide + close + point lights = interesting effect, for both still and video.

So, provided that you get a well assembled sample, this is a STUNNING lens, which has no other market equivalent because of many things it offers: speed, angle of view, close focus abilities.

Totally usable wide open and VERY sharp closed down.

Lee Jay

Registered: January 2007Posts: 16

Sigma 20mm f/1.8 EX DG Aspherical RF review by Lee Jay

Review Date: 1/7/2007

Would you recommend the product? Yes |
Total Spent: $410.00| Rating: 7

Pros:

Pretty good optically, pretty nice FL on 1.6 crop or FF

Cons:

Slow focusing, wierd mechanism

A little soft wide open, but certainly usable. I sold it because the focusing was just terrible in low light.

gadgetguy

Registered: May 2006Posts: 62

Sigma 20mm f/1.8 EX DG Aspherical RF review by gadgetguy

Review Date: 12/3/2006

Would you recommend the product? Yes |
Total Spent: None indicated| Rating: 9

Pros:

20mm and f1.8 - simply no competition

Cons:

slow AF

If you want WIDE and FAST, well, there simpy is no other way to go. IQ is not bad, considering price and the technological breakthroughs (and compromises) for this lens.

AF is not HSM, so it's slow. It also tends to front-focus (at least the copy I had).

NikonEddy

Registered: November 2005Posts: 3

Sigma 20mm f/1.8 EX DG Aspherical RF review by NikonEddy

Review Date: 11/14/2005

Would you recommend the product? Yes |
Total Spent: $279.00| Rating: 9

Pros:

Focal Length, Wide aperture

Cons:

bulky, filter size

Bought purely because its possibly the fastest 20mm available. Its a delight to use. I have used it wide open with no real problems, possibly a little soft on a Film camera (Nikon F4s) but thats to be expected. The lens comes with a sturdy pouch giving good protection if neccessary. No real distortion under normal shooting. It certainly beats any of the opposition as a prime lens. Recommended especially as the lens is now available for £244 now

fstopjojo

Registered: November 2005Posts: 9

Sigma 20mm f/1.8 EX DG Aspherical RF review by fstopjojo

Review Date: 11/2/2005

Would you recommend the product? Yes |
Total Spent: None indicated| Rating: 9

Pros:

Great price for 20mm wide and f1.8 speed, FF compatible, Very sharp from f2.5 (good wide open), Very good contrast, 8" minimum focusing distance a boon, Grippy and wide MF ring with solid stops at each limit, Feels like a tank.

Cons:

No HSM, AF speed and noise are "okay", Dual-Focus clutch mechanism takes getting used to, Some may not like the 82mm size thread and overall bulk of lens, Shadow cast with hood on and internal flash (no problems with hood off or external flash),

Sigma has a good lens here to which Canon really has no answer for. My biggest gripe is the overall "handling" of this 20mm beast with its somewhat large build and clunky "DF" focus mechanism. But all in all, the pros far outweigh the cons and the image quality it produces is very good. I've got a good copy and plan to keep it for a long while.